[LLorenzo]

Quote:

Montipora plate corals are primary targets for many Nudibranchs (Carl, 2008, pers. obs.), and these should be carefully inspected upon arrival. Any areas of exposed skeleton should be checked very thoroughly as this is a good indication that nudibranchs may be present. During daylight hours, Montipora eating Nudibranchs are most commonly found in crevices where they are safe from potential predators. The same applies for egg masses, which are routinely present. Biological treatment: Nudibranchs have several natural predators, including various species of wrasses. Effective treatment of Montipora-eating Nudibranchs with the species Halichoerus chrysus (Golden/Canary wrasse) and Pseudocheilinus hexataenia (Sixline wrasse) has been reported repeatedly. When introducing wrasses to coral systems, the same guidelines apply as described in the Planaria section. As chemical treatment has not been proven to be fully effective, the introduction of predators is preferable. Chemical treatment: Similar to flatworms, Nudibranchs are sensitive to neurotoxic agents such as levamisole (Carl, 2008). Optimal dosages seem to be quite higher for Nudibranchs; a levamisole treatment at 40 mg/l for 4 hours effectively paralyses them. Treatment should be combined with carefully brushing off colonies, to remove Nudibranchs from the corals. At least 4 consecutive dips spread over a month are recommended, as even after such a treatment, Nudibranchs may reappear. A 5% loss of treated corals after 4 dips of 4 hours each was reported by Carl. Iodine solutions such as Lugol's may also be effective, although this has not been proven sufficiently. Treatment should again be combined with brushing off colonies, to remove Nudibranchs. This will also remove egg clusters. Eggs seem insensitive to treatment, therefore the procedure should be repeated at least once a week later to break reproductive cycles by killing young offspring. Freshwater dips for about 10 seconds can also be effective, creating a strong osmotic pressure within the nudibranch tissue. This will also affect coral cells and zooxanthellae, and therefore this treatment should be considered as a last resort. Make sure temperature and pH levels of the water match those of the aquarium from which the animal was collected.

Questo è quanto.. in pratica la rimozione chimica viene comunque accompagnata dalla rimozione manuale e non garantisce un successo pieno, e consiglia di mettere un labride. Le uova sono non risentono del trattamento chimico, ma solo di quello in acqua osmotica, come d'altronde i nudibranchi, ma anche il tessuto del corallo zooxantelle comprese.